Chair



E. THOMPSON.

CHAIR.

APPLICATION FILED 050.20. 1918.

Emma Apr. 26, 1921...

INVENTOR ATTORNEY UITED STTES PATENT orrie.

Specification of Letters Patent.

Patented Apr. 26, 1921.

Application filed December 20, 1918. Serial No. 237,576.

To all whom it may concern:

Be it known that I, EARL THOMPSON, a citizen of the United States, residing at the city of New York, in the county of New York and State of New York, have invented certain new and useful Improvements in Chairs, of which the following is a specifi-v cation.

My invention relates to improvements in chairs, and is particularly adapted for use in school chairs and seats adapted to 0rtho-. pedic treatment and other chairs which are intended to be used continuously for any considerable period of time. In chairs of this character, it is desirable that the back of the occupant be supported in such manner as to relieve the muscles from undue strain and stretching forces and that there be provided adequate support for the lower back to maintain the lumbar curve and adjustable as may be required for each particu- V lar case, to accommodatethe varying anatomical curves, var1at1onof structure and bulk of clothes and no fixed curve can be devised to give proper support to all 1ndividuals. There must be direct support applied where it is most neededv to prevent flexed and twisted positions and each chair should'be fitted to 2. individual user and also adjustable as to the height of the seat so that the legs of the occupant of the chair may rest on the floor in anatural position. It is also important that the back of the chair should be vertical and not be inclined, as this construction tends to cause the user to assume a wrong position and to bring the upper spine, chest and neck forward in an unnatural posture. The upper back of the chair should not extend above the level of the shoulders of the user, but preferably to about that point when seated in a natural position. The chair back should be so constructed as tosupport the back and spine of the occupant in the natural position and maintain the torso, neck and head when seated in the position which should be assumed when standing erect. Neglect or failure'in this respect tends to roduc'e curvature of the spine, scoliosis, mosis and other deformities. The object o my invention is to overcome the conditions which exist in the chairs now in use and to provide a chair which will produce the above mentioned desired results and will prevent and correct spinal curvature and deformity.

I accomplish thisobject' by the device support for the lower back, with parts,

broken away, and F 4; is a section on the line in Fig. 1. imilar characters refer to similar parts throughout the several views.

Referring to the drawings, 1 is a chair having a back formed of two uprights 2 2 which extend to about the level of the shouldersof the occupant of the chair and carry at their upper ends a cross piece 3 pivoted between the uprights 2 2 on pins 4,- 4 which are preferably secured in the cross piece 3 by means of glue or the like and are each provided with ahead 5 which turns freely in the upright 4 and are prevented from belng withdrawn from the upright 4 by means of collars 6 6 therein whereby the cross piece 3 is adapted to swing onthe pivots 4: to adjust itself to the correct chest position and upper back of the occupant of the chair and is limited in its movement by pins 7 inserted in the'uprights 2 or in other suitable manner. Between the uprights 2 and above the seat of the chair, I provide a lumbar rest 8 which is preferably convex in the direction of the front of the chair and is adjustable vertically. For the purpose of vertical adjustment, I prefer to providein the inner face of the upri'ghts;2 a plate 9 having a plurality of perforations or seats 10 to receive the rounded heads 11 of the pins 12 which are mounted in the rest 8 and are normally pressed out into the seats 10 by springs 13 whereby the rest 8 may be adjusted vertically to accommodate the anatomical lumbar curve of the occupant, with space between the seat of the chair and the lumbar rest 8 to accommodate.

the buttocks and clothing. I also preferably provide on the upright 2 adjacent the ends of the rest 8 a guide bar 14 having a longitudinal slot 15 in which slides a set-screw- .16 which may be turned down upon the bar of the chair 1 an extension screw 1 whereby the height of the chair may be adjusted to the occupant.

I have shown the back applied to a chair seat of the usual construction but I do not intend to so limit my invention as it is obvious that it may be applied to chairs of any desired form and is particularly adapted for use in connection with school chairs, orthopedic chairs and the like.

Having thus described my invention, what I claim is- I 1. In a chair, a back, a lumbar rest thereon, a plurality of spring actuated pins seated in said rest and adapted to detachably engage seats in the back, substantially shown and described.

2. In a chair the combination of a back having a plurality of uprights, seats in said uprights, a lumbar rest in the back and newness 3. In a chair, the combination of a back having a plurality of uprights, a cross piece pivoted between the uprights at approximately the height of the shoulders of the occupant and adapted to swing to adjust itself to the normal chest position of the occupant and means for limiting the-swing of the cross piece, and a lumbar rest positioned in the back below the cross piece.

4. In a chair the combination of a back, a cross piece pivoted thereon at approximately the height of the shoulders of the occupant and adapted to swing freely to adjust itself to the normal chest position of the occupant, means for limiting the swing of the cross piece, a lumbar rest positioned on the back below the cross piece, means for adjustably positioning the lumbar rest and means for adjusting the height of the 'chair substantially as shown and described.

In testimony whereof I'aflix my signature.

EARL THOMPSON. 

